Lissamine green

Green S

Names
IUPAC name Sodium 4-[(4-dimethylaminophenyl)-(4-dimethylazaniumylidene-1-cyclohexa-2,5-dienylidene)methyl]-3-hydroxynaphthalene-2,7-disulfonate
Other names Food Green S; FD&C Green 4; Acid green 50; Lissamine Green B; Wool Green S; C.I. 44090; E142
Identifiers
CAS Number	3087-16-9 Y
3D model (Jmol)	Interactive image
ChemSpider	82646 Y
ECHA InfoCard	100.019.463
E number	E142 (colours)
PubChem CID	91525
UNII	9B7E8Y9D0X N
InChI InChI=1S/C27H26N2O7S2.Na/c1-28(2)20-9-5-17(6-10-20)25(18-7-11-21(12-8-18)29(3)4)26-23-14-13-22(37(31,32)33)15-19(23)16-24(27(26)30)38(34,35)36;/h5-16H,1-4H3,(H2,31,32,33,34,35,36);/q;+1/p-1 Y Key: WDPIZEKLJKBSOZ-UHFFFAOYSA-M Y InChI=1/C27H26N2O7S2.Na/c1-28(2)20-9-5-17(6-10-20)25(18-7-11-21(12-8-18)29(3)4)26-23-14-13-22(37(31,32)33)15-19(23)16-24(27(26)30)38(34,35)36;/h5-16H,1-4H3,(H2,31,32,33,34,35,36);/q;+1/p-1 Key: WDPIZEKLJKBSOZ-REWHXWOFAE
SMILES [Na+].[O-]S(=O)(=O)c1ccc4c(c1)cc(c(O)c4/C(=C2\C=C/C(=[N+](/C)C)/C=C2)c3ccc(N(C)C)cc3)S([O-])(=O)=O
Properties
Chemical formula	C27H25N2NaO7S2
Molar mass	576.62 g/mol
Melting point	210 °C (410 °F; 483 K) (decomposes)
Hazards
R-phrases (outdated)	R22
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Green S is a green synthetic coal tar triarylmethane dye with the molecular formula C₂₇H₂₅N₂O₇S₂Na.

As a food dye, it has E number E142. It can be used in mint sauce, desserts, gravy granules, sweets, ice creams, and tinned peas. Green S is prohibited as a food additive in Canada, United States, Japan, and Norway. It is approved for use as a food additive in the EU and Australia and New Zealand.

Green S is a vital dye, meaning it can be used to stain living cells. It is used in ophthalmology, among fluorescein and rose bengal, to diagnose various disorders of the eye's surface.

Green S may cause allergic reactions and is one of the colorants that the Hyperactive Children's Support Group recommends to be eliminated from the diet of children.